1. Field of the Invention
The present invention relates to a work hanging apparatus and a work hanging method for hanging a work such as car stabilizer on a hanger of a hanger line through a movement of the work under a correction.
2. Description of Related Art
Japanese Unexamined Patent Application Publication No. 2011-161616 discloses a work feeding apparatus and a work feeding method that feed works to a hanger line. This related art employs a robot having a hand for holding and three-dimensionally moving a work, a robot controller for controlling the robot, an image taking unit for photographing an image of a hanger conveyed through the hanger line, and a real-time computer for providing the robot controller with a track of the robot's hand.
According to the image of the hanger, the robot controller detects the position and attitude of a hook of the hanger, and according to the detection, feedback-controls the robot so that the robot's hand holding the work may follow the hook of the hanger and hang the work on the hook of the hanger.
The related art conveys a plurality of hangers through the hanger line and safely and surely hangs works on the hooks of the hangers without stopping the hanger line, without regard to the orientation of each hook, and without employing other special facilities. In feeding works to the hanger line, the related art is able to feed works to the hangers independent of manpower and improve the operating speed of the hanger line.
The related art, however, has a limit in correctly hanging a work such as a car stabilizer on the hook of a given hanger of the hanger line because the related art only detects the position and attitude of the hook of the hanger even when the car stabilizer or the like has a small hole with which the hook of the hanger is caught.
In particular, the car stabilizers are generally not required to be precise, and therefore, the small holes of the car stabilizers held even by the robot are erratically positioned. Moreover, when the hanger line is used to paint the car stabilizers, the hangers of the hanger line need a burning process to remove paints adhering to the hangers. This burning process deteriorates and deforms the hangers as aging. Therefore, hanging the car stabilizers on the hangers becomes more difficult due to the deformation of the hangers in addition to the small holes of the car stabilizers that are erratically positioned. This results in deteriorating productivity of the stabilizers.